A suspected Russian spy worked at the U.S. Embassy in Moscow for more than 10 years, according to media reports.

The Russian woman, who was hired by the Secret Service, had access to its intranet and email systems and by default, highly confidential material including the president and vice president’s schedules, the Guardian reported.

However, CNN reported that the woman was not a national security threat and did not have access to highly classified information, according to an unnamed senior administration official.

The woman eventually came under suspicion during a routine security review by the State Department Regional Security Office, when two investigators established she had been having regular, unauthorized meetings with Russia’s main security agency FSB, according to the Guardian.

The senior administration official told CNN that the regional security office alerted the embassy in January 2017 and that the woman was caught red-handed and fired in the summer of that year.

The Guardian reported that the woman was dismissed soon before the Kremlin demanded the expulsion of more than 750 U.S. personnel after Washington imposed more sanctions on Moscow. This provided cover for her removal.

All non-American workers are vetted and employed by the State Department before being assigned work by different agencies.

The State Department declined to comment and said they "do not comment on allegations related to intelligence or personnel matters, and we have no information for you on this alleged incident,” CNN reported.

"At no time, in any U.S. Secret Service office, have FSNs (Foreign Service Nationals) been provided or placed in a position to obtain national security information," the Secret Service said in a statement.

In a later statement, the Secret Service said: "Reports of the timing of the individual's termination in question and the closing of the Secret Service Resident Office in Moscow correlate in any way are false. The U.S. Secret Service Moscow Resident Office closed in August of 2017 due to lack of cooperation from the Russian government - entirely unrelated to the termination of the FSN in question," the statement read. "Reports the Secret Service attempted to minimize or deliberately not disclose the U.S. State Department's findings are categorically false."

The reports came as Russian national Maria Butina, 29, is accused of working as a spy by infiltrating American political organizations, including the National Rifle Association. Last month, a federal magistrate ordered her to be held without bond, pending trial, where she will face two felony charges.

President Donald Trump on Wednesday called on Attorney General Jeff Sessions to shut down Robert Mueller's investigation into Russian interference in the 2016 election, but his aides quickly played down the comments and insisted Trump had no plans to fire the special counsel.

Mueller is investigating Russian attempts to sway the 2016 election toward Trump and whether anyone from Trump's presidential campaign cooperated with Moscow. He is examining whether there were any attempts to obstruct the investigation.

Members of Trump's national security team said that U.S. intelligence officials are worried Russia and perhaps other foreign powers will look to interfere in November's midterm elections. Hours later, Trump accused the media of mischaracterizing his meeting in Helsinki last month with Russian President Vladimir Putin and said relations with Moscow were being hampered by Mueller's probe.